“…(e.g. Sierpinska, 1992;Gagatsis & Shiakalli, 2004;Duval, 2006;Gagatsis, Christodoulou, & Elia, 2013;Gagatsis, Deliyianni, Elia, Panaoura, & Michael-Chrysanthou, 2016;Nicolaou, Gagatsis, Panaoura, Deliyianni, Elia, & Televantou, 2020). It is also reported that the role of representations is very important in problem solving (Elia, Gagatsis, & Demetriou, 2007).…”